Shares Repurchased under Programs (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
	Sep. 30, 2012
Authorized on November 15, 2006
Equity, Class of Treasury Stock [Line Items]
Shares Repurchased	908,399
Total Cost	$ 35.0
Authorized on May 13, 2008
Equity, Class of Treasury Stock [Line Items]
Shares Repurchased	1,027,417
Total Cost	50.0
Authorized on November 11, 2009
Equity, Class of Treasury Stock [Line Items]
Shares Repurchased	972,205
Total Cost	50.0
Authorized on August 11, 2010
Equity, Class of Treasury Stock [Line Items]
Shares Repurchased	1,103,628
Total Cost	50.0
Authorized on November 10, 2010
Equity, Class of Treasury Stock [Line Items]
Shares Repurchased	968,105
Total Cost	50.0
Authorized on May 20, 2011
Equity, Class of Treasury Stock [Line Items]
Shares Repurchased	2,396,143
Total Cost	100.0
Authorized on November 2, 2011
Equity, Class of Treasury Stock [Line Items]
Shares Repurchased	3,136,247
Total Cost	92.1
Repurchase of Equity
Equity, Class of Treasury Stock [Line Items]
Shares Repurchased	10,512,144
Total Cost	$ 427.1